Year	gross (GPI)
1970	1.07003998756409
1971	1.07237994670868
1972	1.07550001144409
1973	1.09078001976013
1974	1.09176003932953
1975	1.13232004642487
1976	1.13065004348755
1977	1.09608995914459
1978	1.08967995643616
1979	1.0901700258255
1980	1.10555994510651
1981	1.10420000553131
1982	1.10046005249023
1983	1.08904004096985
1984	1.0823700428009
1985	1.08377003669739
1986	1.10806000232697
1987	1.08038997650146
1988	1.08162999153137
1989	1.09528005123138
1990	1.07778000831604
1991	1.06582999229431
1992	1.06228995323181
1993	1.06229996681213
1994	1.05952000617981
1995	1.0582799911499
1996	1.06290996074677
1997	1.06315994262695
1998	1.05681002140045
1999	1.04860997200012
2000	1.05243003368378
2001	1.04908001422882
2002	1.06997001171112
2003	1.06616997718811
2004	1.06281995773315
2005	1.07411003112793
2006	1.07658994197845
2007	1.07079994678497
2008	1.06997001171112
2009	1.0495799779892
2010	1.08117997646332
2011	1.08168995380402
2012	1.08221995830536
2013	1.08253002166748
2014	1.08218002319336
2015	1.07465004920959
2016	1.06531000137329
2017	1.06816005706787
2018	1.06008994579315
2019	1.04855000972748
2020	1.04701995849609